Controlled torque gasket compositions



Feb. 24, 1959 -H. w. UNGER ETAL CONTROLLED TORQUE GASKET COMPOSITIONSFiled April 1, 1957 5 M 0 i 1;... Z U n M v United States PatentCONTROLLED TORQUE GASKET COMPOSITIONS Harold W. Unger, Mount Prospect,and Donald H. Zipper, Elmhurst, Ill., assignors to White Cap Company,Chicago, 111., a corporation of Delaware Application April 1, 1957,Serial No. 649,633

35 Claims. (Cl. 215-40) The present invention relates generally toimproved gasket compositions in the form of permanent rubbery gelswhich, forexample, may be derived or produced from plastisols, theimproved compositions being particularly adapted for use in rotatablecaps to provide the same with controlled opening torques followingapplication to glass containers in sealed relation therewith. Morespecifically, the invention is directed to the provision of alubricating coating or film on the sealing surface of the gasket orlining material on the interiors of closure caps, which coating or filmserves to reduce the coeflicient of friction between the gasket and thatpart of the container with which it is in contact. The lubricatingfunction of such coating controls the magnitude of cap-removing torquerequired to loosen and remove thecap from the container to preventseizure between the gasket material and the finish of the containerfollowing application of the cap to the container in known automaticcapping machines such as that disclosed in a copending applicationSerial No. 549,987, filed November 30, 1955.

A lug-type rotatable closure cap with which the improved gasket materialof the present invention is adapted for use is disclosed, for example,in a copending application Serial No. 520,881, filed July 8, 1955. Thistype of cap is formed from a metal shell having a top panel portion anda depending skirt portion, the outer margin of the inner surface of thetop panel portion being provided with gasket material into which ispressed the top rim or edge of a container, such as a glass jar orbottle, when the cap is forced down into sealed relation therewith. Thedepending skirt portion of the cap is provided with inwardly directedlugs which are slidingly moved along glass threads or lugs formed in theouter surface of the container inwardly of the top edge thereof. The capis turned on in a known manner and the advancing of the top panel of thecap toward the top edge of the container brings the gasket into intimatesealing relation with the top edge of the container to seal the same. Insealing glass containers the contents placed in the containers arefrequently at elevated temperatures and the cap including its gasket isalso frequently heated when applied to the container.

In addition to the lug-type caps described, other rotatable caps such asthe internally threaded type may be provided with a controlled openingtorque by means of the improvements to be described. Also, the gasketmaterial may be used in the form of annular side-seal and.

,sealing action with containers. Copolymeric gasket materials includevinyl chloride-vinylidene chloride resins and vinyl chloridevinylacetateresins. Sealing compositions formed from these copolymers may beprepared by following several different procedures which are well known.

Extruded, cast and calendered compositions as well as mixtures commonlyreferred to as plastisols and organosols may be applied to the innersurfaces of caps for container sealing purposes. While several differentforms of vinyl chloride resin base compositions may be improved byfollowing the teachings of the present invention, the plastisolcompositions are specifically dealt with in the following descriptiondue to the adaptability of such compositions to be applied to caps usingthe flowedin technique.

The plastisol gasket materials in use at the present time are made froma paste-forming, resin-plasticizer mixture which preferably and usuallycontains a filler. The mixture, upon fluxing at elevated temperaturesafter being applied to the inner surface of a cap shell, forms apermanent gel which becomes elastic and rubbery upon subsequent cooling.Upon the reheating of the plastisol gasket material, during a sealingoperation requiring heat, when the cap carrying the same is brought intoseating contact with a filled heated jar, the plastisol loses itselasticity until subsequently cooled at which time the originalelasticity is quickly regained. Still further, a plastisol of this typeis known to relax under pressure even when cold. These two inherentphysical phenomena of plastisol gasket materials combine to make itcommercially difficult if not impractical to apply caps having gasketsformed of ordinary plastisols to jars without .either applying the capstoo loosely so that they become leakers or too tightly so that theyfreeze" on and require excessive opening torque to remove.

In order to maintain a seal, hermetic or otherwise, there should besufficient friction to prevent a rotatable closure cap from turning orloosening in ordinary handling. Since there is relatively littlefriction between the metal lugs or threads and glass lugs or threads,the ability of a rotatable cap to stay on a glass container is dueprimarily to the friction between the gasket compound and the glass.Therefore, while there must be sufficient initial friction to prevent acap from being loosened in ordinary handling or from backing off in thecase of inclined lugs on the container, the friction must not increasewith time by seizing to such an extent that the cap is difiicult toremove.

It has been found that the friction caused by seizing developed betweenknown plastisol gasket material and the glass finish increasessubstantially upon standing.

. times as high as 80 inch-pounds. Longer .times have been known torequire inch-pounds or more. As such tests revealed, the values of theopening torque subsequent to the capping operation were found to beextremely variable'and difficult, if not impossible, to control. For useby the average consumer, the ideal opening torque for a rot'atablecapshould fall within a range well below 100 inch-pounds regardless of thetime elapsed following the capping operation. The size of the cap willaffect the magnitude of required opening torque and with the use oflarger size caps the control of opening torque becomes more important.ciples of the present invention, various formulations, given later, havebeen made and flowed into large caps (77 mm. dia.) which were sealedonto jars. Maximum opening torque requirements of these large caps evenover extended periods of storage time were found to be substantiallyless than 100 inch-pounds. This approaches the ideal range even though alarge size cap was used. This range of opening torque is such that thereis sufficient adhesioh to prevent the cap from backing off out.

Using the .prinof sealing engagement with the container in the case ofinclined lugs and from becoming accidentally loosened in handling, andyet the adhesion may be readily overcome without difficulty uponintended removal of the cap from .the container.

Plastisol gasket materials .fformed from resins .such as polyvinylchloride exhibit good initial elasticity when cold but quickly lose thiselasticity under constant deformation whilesharplylosing thesame whenheated to around '190 F. Elasticity is sharply regained upon cooling andthe original properties reassert themselves. Whilethe .compressive forceexerted against the gasket material Will cause the same to relax evenwhile cooling, the degree of relaxation is not sufficient tocounterbalance the increased adhesiveness caused by the elasticity beingquickly regained. Consequently, the compressive force developed by theregaining of elasticity greatly exceeds the reduction .in compressiveforce caused by relaxation during the cooling of the plastisol gasketmaterial.

TWithfincreased compressive force between the plastisol gasket and theglass finish, seizure or friction increases correspondingly. Thus, uponstanding, the torque necessary to remove a cap from a containerincreases proportionally with increased seizure or adhesiveness. This istrue also whenvthe cap is not heated, but the opening torques do notreach quite as high values and it takes more time-for the highest valueto be obtained. During a hot capping operation the plastisol, being in aheated condition, exhibits minimum adhesiveness. Consequently, it isnecessary to rely on the friction developed by the torque applied inturning the cap down on the container. This torque must be adequate inmagnitude to establish sufficient friction between the cap and containerto prevent loosening or movement of the cap following the cappingoperation until sufiicient adhesiveness develops betweenthe plastisoland the container by the regaining of elasticity upon cooling. This isnot a problem in cold sealing, but controlling the tightening torque isvery important. has been found impractical, if not impossible, whenknown plastisol compositions are used, to control the friction developedbetween the gasket and the container due to the sharp regaining ofelasticity of the plastisol upon cooling. Until recently, there has beenno known procedure to follow, or published formulations to use, toproduce capped containers, the caps of which may be removed from thecontainers by the application of open ing torques falling within aspecified, relatively limited and desirable range. It is during thefirst minute or so following the heated capping operation that adhesionis begun. In the case of cold capping, the adhesion develops moreslowly.

It is an object of the present invention to provide improved gasket orsealing compositions which, when applied to the interior'ofa closure capin accordance with known practices and the cap is thereafter applied toa container by commercial automatic capping apparatus, provide acontrolled frictional seal between the gasket material and the containerwhich may be overcome by the use of a torque falling within apredetermined relatively limited and acceptable range at any timefollowing the capping operation regardless of the compressive forces onthe gasket against the sealing surface that may result.

Another object is to provide an improved sealing gasket composition suchas the plastisol or organosol type which exhibits controlled seizureupon use in a known manner in sealing a container, the frictiondeveloped between the cap and .the containerbeing capable ofpredetermination to allow the cap to .be removed at any time subsequentto the capping operation upon the application of an opening torque whichfalls within a relatively limited and useful range, the controlledopening torque resulting from the presence of .alubricating interfacebetween .the gasket :composition .and .the container, which interface Aspreviously described, it

' gara es is capable of controlling the magnitude of frictionalresistance developed between the cap and the container while allowingthe development of frictional resistance of sufiicient magnitude toestablish and maintain efficient sealing action between the cap andcontainer.

A further object is to provide improved gasket compositions of the typeformed from a paste-forming resinplasticizer mixture containing discreteparticles of filler material, the mixture being improved by theinclusion of lubricant which will be present on the surface of theresulting rubbery gel upon fiuxing and cooling of the mixture ortransforming of the mixture into a'permanent rubbery gel by extrusion orthe like, the lubricant being either lecithin or silicone fluid orcombinations of lecithin, silicone fluid and paraflin, the lubricatingagents or combinations of the same providing a controlled frictioncoating on the sealing surface of the gelled gasket composition to allowcontrolled torque removal of a cap carrying the composition followingapplication of the same in sealed relation with a glass container.

Another object of the invention is the provision of rotatable closurecaps having gaskets or sealing linings formed of the compositionsmentioned in the foregoing objects.

Other objects not specifically set forth will become apparent from thefollowing detailed description of the present invention made inconjunction with the drawing wherein:

Fig. 1 is a side elevational view of a glass container hermeticallysealed with a closure cap of the type par ticularly adapted for use inpracticing the present inventio-n;

Fig. 2 is a top plan view of the closure capflshown in Fig. 1;

Fig. 3 is .a bottom plan view of theclosure cap shown in Fig. 1;

Fig. 4 is a fragmentary sectional view of the closure cap on enlargedscale taken along line 44 of Fig. 2; and

Fig. 5 is a view similar to Fig. 4 illustrating container sealingapplication of the closure cap.

In Fig. 1 a glass container 10, such as an ordinary jelly glass, issealed with a closure cap 11. The closure cap 11 is of the typepreviously described and as partic ularly shown in Figs. 24'consists ofa cap body or shell having a top panel portion 12 and a depending skirtportion 1?. The cap body or shell is stamped out from suitable coatedtin plate, although other materials may be used. Generally, the tinplate is enameled on the exterior and the interior is enameled or coatedwith a known lacquer-formulation so as to form a protective coating andgive the interior attractiveness in appearance. The bottom edge of thedepending skirt 13 is normally. rolled to reinforce this edge whilegiving the same a neat appearance and removing the sharp edge which isleft' when the cap shell or body is stamped out. The lug-type closurecap illustrated is provided with a plurality of lugs- 14 for cooperativecap clamping engagement with circumferentially spacerd glass lugs 15integrally formed.

on the exterior of the neck portion of the glass container 16) as shownin Fig.5.

The top panel 12 of the cap 11 is provided with a central depressedportion 16 which defines a continuous annular shoulder 17 inwardly ofthe skirt 13. The

shoulder 17 and skirt 13 thus define therebetween an an the cap 1 to thecontainer 10 isshown in Fig. SWith the top edgeof the neckof thecontainer 10 (which is generally referred to as the sealing 'finish)being embedded in'the gasket .19. Removal of the cap 11 from thecontainer 10 requires the -application'of a torque and,

as previously described, the present invention is directed to thecontrolling of the opening torque within a specified range to permitsubstantial uniformity in opening torques required for caps of the typedescribed.

A plastisol of the type described above is in the form of a congealedpaste-forming, resin-plasticizer mixture containing, in uniformdistribution, finely divided discrete particles of a filler material andfinely divided discrete particles of a paste-forming, synthetic resinsuspended in a non-volatile plasticizer for the resin, the resin beingpaste-forming with the plasticizer at a temperature below the fiuxingtemperature of the resinplasticizer component and soluble in theplasticizer upon heating to the fluxing temperature. This type ofplastisol forms at the resin-plasticizer fluxing temperature a permanentgel which becomes elastic and rubbery upon subsequent cooling.

It has been found that by adding to the foregoing conventional mixtureof ingredients forming a plastisol certain lubricant-formingingredients, upon the formation of the gel following fiuxing of themixture, a lubricant will be present on the sealing surface thereof toprovide an outer coating capable of lubricating the frictional sealbetween the gasket and a glass finish or other sealing surface. Theextent of lubrication is such that the necessary tack or adhesivenesscapable of resisting loosening or dislodgement of the applied capfollowing the capping operation is present while at the same time thefrictional forces developed between the gasket and the sealed surfacecan be readily overcome upon the application of an opening torque ofrelatively low magnitude.

As shown in Figs. 4 and 5, the lubricant is in the form of a surfacecoating 21 present on the sealing surface of the gasket 19 for directcontact with the sealing finish of the container 10. The lubricant formsan interface which remains between the plastisol and containersubsequent to the full recovery of the elasticity and accompanyingcompressive force of the plastisol gasket. In order to remove the capfrom the container, it is necessary merely to apply a torque adequate toeffect internal shearing in the lubricant interface and overcome thefriction existing between the lugs of the cap and the threads of thecontainer. Thus, while the friction existing between the lugs of the capand the threads of the container is controlled to a predetermined extentby the capping operation, the friction existing between the plastisolgasket material and the glass finish is controlled by the type oflubricant-forming ingredients incorporated in the gasket material andthe extent to which the lubricant is present on the sealing surface ofthe gasket material. The opening torque is the force necessary toovercome the sum of these predetermined frictional resistances and maybe readily predicted and controlled to fall within an idealopening-torque application range.

-The preferred lubricants and mixtures of lubricants constituting theessence of the pres-cut invention include the use of lecithin, siliconefluid and a sealing wax such as parafim. The preferred combination oflubricants includes the use of all three in admixed form. However,desirable results can be obtained by using lecithin alone, a siliconefluid alone, as well as mixtures of lecithin and silicone fluid,lecithin and paraffin, and silicone fluid and parafiin. The lubricantsor lubricant-forming ingredients referred to above not only exhibit thedesirable property of controlling friction but, still further, meet manyother requirements of a material used on food containers. They are, forexample, non-thermosetting, non-toxic and nondrying.

In forming a plastisol gasket composition, a polyvinyl chloride resin ispreferably used; however, this resin may be readily modified with amaterial such as polyvinylidene chloride or polyvinylacetate. Polyvinylchloride resin in combination with a copolymer resin of vinyl chlorideand vinylidene chloride forms an effective plastisol material as willsubsequently be described. The resin forms a paste with the plasticizerand is added thereto in the form of finely divided discrete particleswhich become uniformly distributed in suspension in the plasticizer. Anysuitable plasticizer may be utilized as long as it is non-volatile.Plasticizers such as Paraplex G-62 (a polyester epoxide made by Rohm andHaas, Philadelphia, Pennsylvania) and Citroflex A-4 (an acetyltributylcitrate made by Chas. Pfizer and Company, Brooklyn, New York) have beenfound suitable. A filler material may be added in the form of finelydivided discrete particles which are uniformly distributed throughoutthe mixture. A filler material such as barytes has been found to impartdesirable flow properties to the mixture. The resin used should besubstantially insoluble in the particular plasticizer at atmospherictemperatures while being soluble in the plasticizer at elevated fluxingtemperatures.

On the basis of parts by weight of resin, the plasticizer used willpreferably fall within the range of 50 to 250 parts by weight. Thefiller material is preferably added in quantities within the range of 0to 250 parts by weight. To the resin plasticizer mixture, which isformulated in any known manner, is added a quantity of lubricant theamounts of which will vary depending upon the particular lubricant ormixture of lubricants used as well as the amount of resin, filler orplasticizer present. In connection with the use of lecithin of acommercial grade and form, it has been found that about 0.25% by weightof the plastisol composition and greater yields desirable result. Theupper level of lecithin added to the plastisol composition will dependupon the extent to which certain physical properties of the plastisolcan be sacrificed. With the use of excessive amounts of a lubricant orlubricating mixture, the modulus, hardness and tensile strength of theplastisol may be adversely affected. Consequently, the. upper limit towhich lubricant may be present in the composition will depend upon itsuntoward effect on the physical properties of the finished gasketmaterial.

In connection with the useof silicone fluid it has been found thatquantities of from about 0.5% to 15% by Weight of the composition arepreferably used. Quantities of from about 1% to 10% of paraffin based onthe total weight of the composition are preferably used. Amounts ofthese lubricants including lecithin falling within the ranges specifiedprovide a well balanced lubrication system in the plastisol compositionwhether or not certain of the particular lubricants, such as lecithinand silicone fluid, are used separately or any combinations of the sameare used in admixture.

The preferred silicone fluid is that having a viscosity of approximately350 centistokes although other viscosities capable of providing thedesired lubricating action can be incorporated in the plastisolcomposition. Commercial grades and forms of lecithin have been found tobe entirely suitable. While the wax lubricating ingredient is preferablyparafiin, other waxy ingredients can be used. Examples of suchingredients are longchain fatty acids such as stearic acid and myristicacid, diglycol stearate, beeswax, polyamide wax, candelilla wax,octadecenylamine, polyethylene glycol, japan wax, long-chain alcoholsuch as stearyl and cetyl alcohols, and blended parafiins.

Upon complete mixing of the resin-plasticizer mixture including thelubricant, the paste-like composition formed is readily adapted forapplication to the interior of a closure cap shell to form an annulargasket or sealing lining. The particular manner in which such apastelike mixture is applied to the cap is known and discussed, forexample, in said copending application. The mixture exhibits adequatetackiness to adhere to the enameled surface of the cap and be retainedin position during subsequent fiuxing procedures at which time themixture is transformed into a permanent rubbery gel. The fluxing of theresin-plasticizer mixture is completed when the plastisol reaches atemperature of approximately aortas-s 350 'F., and lubricant 'will bepresent on'the surface of the gasket ring or lining carried on the capand re mains thereon following subsequent cooling of the finished'gasket and cap. The surface coating or film of lubricant being viscousremains on the surface of the gasket material and storage overprotracted periods of time will not result in noticeably reducedlubricating efficiency when the cap is ultimately used in sealing acontainer.

The following examples illustrate typical plastisol compositions towhich various lubricants and mixtures of lubricants of the typedisclosed have been added in accordance with the principles of thepresent invention. The particular ingredients and amounts used as wellas conditions and procedures described herein are merely illustrativeand are not intended to limit the scope of the present invention.

A basic plastisol composition was used in a series of tests usingdifferent lubricants and combinations thereof wherein 77 mm. rotatablecaps having four lugs were provided with the various plastisol gasketsand applied to similar glass jars having helical lugs. In each instancecalcium chloride was added to the jar to dry out any moisture thereinwhich might affect the particular test and the test cap was applied tothe jar under vacuum by a known type of capping machine. The cappedcontainers were then allowed to stand for certain time intervals and theopening torques necessary to remove the caps from the jars were measuredin inch-pounds.

Basic recipe In the foregoing basic recipe, the Geon 121 is a commercialpolyvinyl chloride resin manufactured by Goodrich Chemical Co.,Cleveland, Ohio. The (icon 202 is a copolymer resin containingapproximately 94% vinyl chloride and 6% vinylidene chloride, this resinbeing available from the same source as the polyvinyl chloride. TheFerro 707X is a stabilizer soap made by Ferro Chemical Co., Bedford,Ohio. While this particular stabilizer is preferred, calcium ricinoleatemay be used. The Titanox RA is a titanium dioxide pigment manufacturedby Titanium Pigment Corporation, New York, .New York.

The following table sets forth the opening torques required in removingthe various caps applied to the containers as previously described. Ineach instance the basic recipe listed above was used and the parts byweight of L (lecithin), S (silicone fluid) and P (paraffin) used in eachformulation is set forth.

Opening torques (in.-lb.)

Opening Age in P,4.4 P-A S 2.5 P-4.4 Days 8-2.5 L-LO L1.0 Ll.0 S -2.58-2.5

opening torques in inch-pounds were below '100 inchpounds andsubstantially .below'with those formulations including lecithin. Withoutthe 'use of a lubricant or mixture of lubricants in the basic recipe,the opening torque necessary to remove a cap from a container would beover inchpounds. Consequently, the results ob tained indicate asignificant improvement in the reduction in opening torque whilemaintaining efficient sealing action between the cap and container. Theparafiin used in the test was of a commercial grade available fromStandard Oil of Indiana and the silicone fluid was a 350 centistokecompound manufactured by Dow Corning, Midland, Michigan. The lecithinwas a commercial grade obtained from Glidden Corporation, Soya Division,Chicago, Illinois.

It has been found that in using silicone fluid alone as a lubricant,substantially larger quantities thereof than of lecithin alone arenecessary in order to provide comparable lubricating action. The use ofparaiiin alone is not considered desirable in that, upon blooming of thewax to the surface of the gasketing material and upon application of thecap to the jar, the paraffin sets up as a solid at the interface whichrequires excessive torque for shearing in order to remove the cap fromthe jar. However, the inclusion of parafiin provides for easier capapplication onto the container. Consequently, the preferred lubricatingmixture includes an amount of paraflin combined With lecithin andsilicone fluid.

During extended testing of the various plastisol compositions of thepresent invention, it has been foundthat it is desirable to increase theamount of lubricants when the plasticizer-resin and/or plasticizerfiller ratios are increased. Thus, it is desirable to maintainapproximately the same percentage by weight of lubricant in the over-allplastisol composition. in general, an increase in plasticizer and/ orfiller requires a relative increase in lubricant.

While the use of the improved compositions has been described primarilyin connection with lug-type caps, it should be understood that thecontrolled opening torques obtainable therewith are also useful withother forms of caps, such as screw caps. I

Obviously, many modifications and variations of the invention ashereinbefore set'forth may be made without departing from the spirit andscope thereof, and therefore only such limitations should be imposed asare indicated in the appended claims.

We claim:

l. A gasket forming composition comprising a vinyl chloride base resinand quantities of lecithin and silicone fluid, the latter ingredientsbeing present in sufficient amounts so as to be present on the surfaceof a gasket formed from said composition and provide lubricationthereto.

2. A gasket forming composition comprising a vinyl chloride base resinand quantities of lecithin, silicone fluid and parafiin, the latteringredients being present in sufficient amounts so as to be present onthe surface of a gasket formed from said composition and providelubrication thereto.

3. A gasket forming composition comprising a vinyl chloride base resinand quantities of silicone fluid and paraiiin, the latter ingredientsbeing present in sufficient amounts so as to be present on the surfaceof a gasket formed froin'said composition and provide lubricationthereto.

4. A gasket forming composition comprising a vinyl chloride base resinand quantities of lecithin and paraffin, the latter ingredients beingpresent in sufficient amounts so as to be present on the surface of agasket formed from said composition and provide lubrication thereto.

5. A gasket forming'composition comprising a vinyl chloride base resinand a quantity of silicone fluid, the latter ingredientbeing present ina sufiicient amount'so as to be present on the surface of a gasketformed from said composition and provide lubrication thereto.

6. A gasketforming composition comprising a vinyl chloride base resinand quantities of lecithin and silicone fluid, the lecithin beingpresent in an amount not less than about 0.25 by weight and the siliconefluid being present in an amount of from about 0.5% to 15% by weight soas to be present on the surface of a gasket formed from said compositionand provide lubrication thereto.

7. A gasket forming composition comprising a vinyl chloride base resinand quantities of lecithin and parafiin, the lecithin being present inan amount not less than about 0.25% by weight and the paraflin beingpresent in an amount of from about 1% to 10% by weight so as to bepresent on the surface of a gasket formed from said composition andprovide lubrication thereto.

8. A gasket forming composition comprising a vinyl chloride base resinand quantities of lecithin, silicone fluid and paraffin, the lecithinbeing present in an amount of not less than about 0.25% by weight, thesilicone fluid being present in an amount of from about 0.5% to byweight, and the paraflin being present in an amount of from about 1% to10% by weight, these latter ingredients being present on the surface ofa gasket formed from said composition in sufficient amounts to providelubrication thereto.

9. A gasket forming composition comprising a vinyl chloride base resinand a quantity of silicone fluid, the latter ingredient being present inan amount of from about 0.5 to 15 by weight so as to be present on thesurface of a gasket formed from said composition and provide lubricationthereto.

10. A gasket forming composition comprising a vinyl chloride base resinand quantities of silicone fluid and paraflin, the silicone fluid beingpresent in an amount of from about 0.5 to 15 by weight and the parafiinbeing present in an amount of from about 1% to 10% by weight so as to bepresent on the surface of a gasket formed from said composition andprovide lubrication thereto.

11. A gasket forming composition comprising a vinyl chloride base resinand approximately 1 part by weight of lecithin, approximately 2.5 partsby weight of silicone fluid, and approximately 4.4 parts by weight ofparaffin, said lecithin, silicone fluid and paraffin being present onthe surface of a gasket formed from said composition in sufficientamounts to provide lubrication thereto.

12. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the outer surface of which is adapted forfrictional sealing engagement with a surface of said container, saidouter surface being provided with a lubricant coating comprisinglecithin and silicone fluid.

13. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the outer surface of which is adapted forfrictional sealing engagement with a surface of said container, saidouter surface being provided with a lubricant coating comprisinglecithin, silicone fluid and paraflin.

14. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the outer surface of which is adapted forfrictional sealing engage ment with a surface of said container, saidouter surface being provided with a lubricant coating comprisinglecithin and paraffin.

15. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the outer surface of which is adapted forfrictional sealing engagement with a surface of said container, saidouter surface being provided with a lubricant coating of silicone fluid.

16. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the outer surface of which is adapted forfrictional sealing engagement with a surface of said container, saidouter surface being provided with a lubricant coating comprisingsilicone fluid and paraffin.

17. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin andrelatively small quantities of lecithin and silicone fluid sufficientfor lubrication being present on the surface of said sealing materialwhich is arranged for frictional sealing engagement with a surface ofsaid container.

18. A closure member adapted for turn-on application to a container insealing relation therewith, said member having applied to an innersurface thereof a sealing material formed of vinyl chloride base resin,a quantity of lecithin of not less than about 0.25 by weight, and aquantity of silicone fluid of from about 0.5 to 10% by weight,sufficient of said lecithin and silicone fluid for lubrication beingpresent on the surface of said sealing material which is arranged forfrictional sealing engagement with a surface of said container.

19. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin andrelatively small quantities of lecithin and paraffin sufficient to bepresent on the surface of said sealing material which is arranged forfrictional sealing engagement with a surface of said container.

20. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin, aquantity of lecithin of not less than about 0.25% by weight, and aquantity of paramn of from about 1% to 10% by weight, sufficientlecithin and paraflin for lubrication being present on the surface ofsaid sealing material which is arranged for frictional sealingengagement with a surface of said container.

21. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin andrelatively small quantities of lecithin, silicone fluid and paraffinbeing present on the surface of said sealing material which is arrangedfor frictional sealing engagement with a surface of said container.

22. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin, aquantity of lecithin of not less than about 0.25 by weight, a quantityof silicone fluid of from about 0.5% to 10% by weight, and a quantity ofparaffin of from about 1% to 10% by weight, suflicient lecithin,silicone fluid and paraflin for lubrication being present on the surfaceof said sealing material which is arranged for frictional sealingengagement with a surface of said container.

23. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin and arelatively small quantity of silicone fluid being present on the surfacethereof which is arranged for frictional sealing engagement with asurface of said container.

24. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin and aquantity of silicone fluid of from about 0.5 to 15% by weight,suflicient silicone fluid for lubrication being present on the surfaceof said sealing material which is arranged of said sealing materialwhich is arranged for frictional 7.

sealing engagement with a surface of said container.

26. A closure member adapted for application to a container in sealingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin, aquantity of silicone fluid of from about 0.5% to 10% by Weight, and aquantity of paraffin of from about 1% to 10% by Weight, suflicientsilicone fluid and parafiin for lubrication being present on the surfaceof said sealing material which is arranged for frictional sealingengagement with a surface of said container. 7

27. A gasket forming composition comprising a vinyl chloride base resinand suflicient quantities of lecithin and parafiin so as to be presenton the surface of a gasket formed from said composition and providelubrication thereto, the paraffin content being approximately 2% byweight.

28. A gasket forming composition comprising a vinyl chloride base resinand suflicient quantities of lecithin and parafiln so as to be presenton the surface of a gasket formed from said composition and providelubrication thereto, the lecithin content being approximately 0.5% byweight.

29. A gasket forming composition comprising a vinyl. chloride base resinand quantities of lecithin and paraffin, the lecithin being present atabout 0.5% by weight and the par-aflin being present at about 2% byWeight so as to bepresent on the surface of a gasket formed from saidcomposition and provide lubrication thereto.

30. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the outer surface of which is adapted forfrictional sealing engagement with a surface of said container, saidouter surface being provided with a lubricant coating comprisingparafiin and about 0.5% by weight lecithin.

31. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby the gardens l2 outer surface of which isadapted for frictional sealing engagement with a surface of saidcontainer, said outer surface being provided with a lubricant coatingcomprising lecithin and about 2% by weight paraflin.

32. A rotatable cap adapted for application to a container in sealingrelation therewith, said cap having a vinyl chloride base gasketmaterial carried thereby, the outer surface of which is adapted forfrictional sealing engagement with a surface of said container, saidouter surface being provided with a lubricant coating comprising about0.5% by weight lecithin and about 2% 'by weight paraffin.

33. A closure member adapted for application to a container in sealingrelation therewith, said member 'having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin andrelatively small quantities of lecithin and paraffin sufficient to bepresent on the surface of said material which is arranged for frictionalsealing engagement with a surface of said container, the quantity oflecithin being about 0.5% by weight.

34. A closure member adapted for application to a container in scalingrelation therewith, said member having applied to an inner surfacethereof a sealing material formed of vinyl chloride base resin andrelatively small quantities of lecithin and paraffin sufficient to bepresent on the surface of said sealing material which is arranged forfrictional sealing engagement with a surface of said container, thequantity of parafiin being about 2% by weight.

35. A closure member adapted for application to -a container in sealingengagement therewith, said member having applied to an inner surfacethereof a scaling material formed of vinyl chloride base resin andrelatively small quantities of lecithin and paraflin' sufficient to bepresent along the surface of said sealing material which is arranged forfrictional sealing engagement with a surface of said container, thequantity of lecithin being about 0.5 by weight and the quantity ofparaffin being about 2% by weight.

References Cited in the file of this patent UNITED STATES PATENTS2,489,407 Foye Nov. 29, 1949 2,752,059 j Schneider June 26, 1956 FOREIGNPATENTS 566,048 Great Britain Dec. 11, 1944 669,600 Great Britain Apr.2, 1952

